Japanese patent application publication No. 2016-132221 discloses one example of an inkjet recording apparatus provided with refillable ink tanks. A user injects ink from an ink bottle into an ink chamber of the ink tank through an inlet formed in the ink tank. The conventional inkjet recording apparatus also prompts the user to indicate whether the ink chamber has been refilled with ink when inferring that a refilling process has been performed. In response to the user operation to indicate that the ink chamber has been refilled, the conventional inkjet recording apparatus initializes a count value indicative of a residual ink quantity for the ink chamber.